Method for color matching of bright paint

ABSTRACT

The following steps ( 1 ) to ( 3 ) are executed by using a computer toning apparatus constituted by (A) a calorimeter, (B) micro-brilliant-feeling sample-color tags, and (C) a computer in which a plurality of paint blendings, color data and micro-brilliant-feeling data corresponding to the paint blendings, and color characteristic data and micro-brilliant-feeling characteristic data of a plurality of primary-color paints are entered and a color-matching logic works: (1) a step of measuring a reference color with which a paint color should be matched by a colorimeter and obtaining the color data of the reference color, (2) a step of comparing the reference color with the micro-brilliant-feeling sample-color tags and deciding the micro-brilliant feeling of the reference color, and (3) a step of comparing the color data and micro-brilliant feeling of the reference color with the color data and micro-brilliant feeling data corresponding to the paint blendings previously entered in the computer, and selecting a prospective paint blending.

TECHNICAL FIELD

[0001] The present invention relates to a computer toning apparatus anda toning method of a paint having brilliant feeling using microbrilliant-feeling sample-color tags.

BACKGROUND ART

[0002] A color matching system using a computer is publicly known asdescribed in the specification of U.S. Pat. No.3,601,589. The above USPatent discloses a method in which all spectral reflectances of anunknown color panel are decided by a scanning spectrophotometer and sentto a computer, and the computer mathematically processes previouslystored data showing K-value (indicating “light absorption factor”) andS-value (indicating “light scattering factor”) to perform logical colormatching.

[0003] The disclosed contents of the above US Patent basically relate toa series of computing procedures. That is, according to the computingprocedures, it is possible to compute K-value and S-value for each ofspectral wavelengths and moreover decide K- and S-values of acombination of a pair of pigments so that the values become equal to K-and S-values of an unknown color for each of the above spectralwavelengths. This is a basic color-matching algorithm used for otherspectral-light-intensity-based color matching systems.

[0004] The system according to the above US Patent has the following twoproblems: the first problem is that the system is very expensive and themaintenance of the system is difficult and the second problem is thatlogical color matching is performed by using the data of an unknowncolor obtained for a known pigment. That is, a color finally obtained bymixing pigments in accordance with a color value obtained by computationmay become a color different from the above unknown color. Therefore,because the above color-matching formula is a primary mathematicalapproximation method, it is normally necessary to correct and adjust thesystem.

[0005] To improve the system, the official gazette of Japanese PatentLaid-Open No. 153677/1989 discloses a method and an apparatus ofanalyzing a selected color by a portable color meter, storing the colordata showing the hue, chroma, and lightness of the selected color,connecting the color data in the color meter to a computer, storing aplurality of usable color formulas (paint blending) in the computer,storing the data showing hues, chromas, and lightnesses of paintsdesignated by the stored usable color formulas in the computer, findingthe most approximate matching by comparing the data of the selectedcolor received from the color meter with the stored color data showingthe stored usable color formulas, selecting a stored color formula shownby the color data found as the most approximate matching, and therebyperforming color matching for the selected color.

[0006] Moreover, as paint colors of automobiles, the number of paintcolors having brilliant feeling is recently increased in which aluminumpowder or brilliant mica is blended from the viewpoints ofdiversification of personal tastes and improvement of beauty. Whenperforming color matching to repair-paint the paint colors havingbrilliant feeling, the color-matching accuracy of the color-matchingmethod disclosed in the official gazette of Japanese Patent Laid-OpenNo. 153677/1988 is not sufficient yet and a color-matching method forpaint colors having brilliant feeling by a computer has not beenproposed so far. Moreover, there is a problem that toning of a paintcolor having brilliant feeling is difficult for an immature toningperson.

[0007] Furthermore, because a marketed calorimeter cannot performmeasurement separate from brilliant feeling, micro brilliant feelinge.g. graininess of aluminum) may not be frequently adjusted though acolor is toned.

[0008] It is an object of the present invention to provide a computertoning method capable of accurately toning a paint color havingbrilliant feeling and allowing an immature toning person to easilyperform toning.

DISCLOSURE OF THE INVENTION

[0009] The present inventor found that the above object can be achievedby using a computer toning apparatus constituted by a calorimeter, microbrilliant-feeling sample-color tags, and a computer to which variouspaint blendings and paint-color data values are input and in which acolor-matching computation logic works and finished the presentinvention.

[0010] That is, the present invention provides a toning method of apaint having brilliant feeling (hereafter may be referred to as a firsttoning method), characterized by executing the following steps (1) to(3) by a computer toning apparatus constituted by (A) a calorimeter, (B)micro brilliant-feeling sample-color tags, and (C) a computer in which aplurality of paint blendings, color data and micro brilliant-feelingdata, and color characteristic data of a plurality of primary colors andmicro brilliant-feeling characteristic data are entered and acolor-matching computation logic using the paint blendings and the datavalues works. That is, the present invention comprises:

[0011] (1) a step of measuring a reference color to which a paint colorshould be adjusted through toning by a colorimeter and obtaining thedata of the reference color;

[0012] (2) a step of comparing the reference color with microbrilliant-feeling sample-color tags and deciding the micro brilliantfeeling of the reference color; and

[0013] (3) a step of comparing the color data and micro brilliantfeeling of the reference color with the color data and microbrilliant-feeling data corresponding to paint blendings previouslyentered in a computer, indexing matching degrees between colors andmicro brilliant feelings of the entered paint blendings, and selecting aprospective paint blending.

[0014] Moreover, the present invention provides the above toning methodcharacterized by executing (4) a step of correcting the selectedprospective paint blending by using a color-matching computation logicand obtaining a corrected blending closer to a reference color after theabove step (3).

[0015] Furthermore, the present invention provides the above toningmethod characterized by transferring the prospective corrective paintblending obtained in the step (3) or the corrected blending obtained inthe step (4) to an electronic balance.

[0016] Furthermore, the present invention provides a toning method of apaint having brilliant feeling (hereafter may be referred to as secondtoning method) characterized by executing the following steps (5) to (7)by a computer toning apparatus constituted by (A) a colorimeter, (B)micro brilliant-feeling sample-color tags, and (C) a computer in which aplurality of color numbers, paint blendings correspond to the colornumbers, color data and micro brilliant-feeling data corresponding tothe paint blendings, and color characteristic data and microbrilliant-feeling data of a plurality of primary-color paints areentered and a color-matching computation logic using the paint blendingsand the data values works. That is, the present invention comprises:

[0017] (5) a step of measuring a reference color to which the color of apaint should be adjusted by a colorimeter through toning and obtainingthe data of the reference color;

[0018] (6) a step of comparing the reference color with microbrilliant-feeling sample-color tags and deciding the micro brilliantfeeling of the reference color; and

[0019] (7) a step of selecting the color data and microbrilliant-feeling data of at least one paint blending having the colornumber same as the preset color number of the reference color, comparingthe color data and micro brilliant-feeling data of the selected paintblending with the color data and micro brilliant feeling of thereference color, indexing the matching degree between the color and themicro brilliant feeling of the selected paint blending, and selecting aprospective paint blending.

[0020] Furthermore, the present invention provides the above toningmethod characterized by executing (8) a step of correcting the selectedprospective paint blending by a color-matching logic and obtaining acorrected blending closer to a reference color after the above step (7).

[0021] Furthermore, the present invention further provides the abovetoning method characterized by transferring the prospective paintblending obtained in step (7) or the corrected blending obtained in step(8) to an electronic balance.

BEST MODE FOR CARRYING OUT THE INVENTION

[0022] A toning method of the present invention is described below indetail.

[0023] A toning method of the present invention is a method for toning apaint having brilliant feeling capable of forming a brilliant paint filmby using a colorimeter (A), micro brilliant-feeling sample-color tags,and a computer (C) in which a color-matching logic works to be describedlater.

[0024] The above paint having brilliant feeling can use any one ofpaints containing brilliant pigments having brilliant feeling andinterference action such as flaky aluminum powder, vapor-depositionaluminum powder, colored aluminum powder, mica-like iron oxide, micapowder, metal-oxide-covered mica powder, metal-oxide-covered silicaflake, and brilliant graphite, brilliant-material powder such asmetallic powder such as copper powder, and coloring pigment according tonecessity.

Colorimeter (A)

[0025] A colorimeter (A) is a unit for obtaining the color data of apaint film by measuring the color of the paint film and it is possibleto use any known calorimeter as long as it can achieve the above object.

[0026] It is preferable to use a multi-angle calorimeter capable ofmeasuring many angles as a colorimeter. In the case of the multi-anglecalorimeter, measurement is performed under two or more conditions inwhich two or more angle conditions, usually two to four angleconditions, that is, incident angles of the light to be measured aredifferent from each other or two or more conditions in whichright-receiving angles formed between a mirror-surface reflection axisand a light-receiving axis are different from each other. Themirror-surface reflection axis is an axis for forming a reflection anglewhen an incident angle and the reflection angle are equal to each other,that is, an axis in which the reflection angle is 45° when the incidentangle is 45°.

[0027] To change light-receiving angles, the angle condition is notrestricted. In general, however, the following cases are preferablebecause it is easy to correspond to determination of a color accordingto visual observation: when there are two angle conditions, these twoconditions are applied to ranges of the light-receiving angle between15° and 30° and between 75° and 110° one each; when there are threeangle conditions, these conditions are applied to ranges of thelight-receiving angle between 15° and 30°, between 35° and 60°, andbetween 75° and 110° one each; and when there are four angle conditions,these conditions are applied to ranges of the light-receiving anglebetween 15° and 30°, between 35° and 60°, between 70° and 80°, andbetween 90° and 110° one each.

[0028] Each measured value (angular reference measured value) obtainedby measuring the color of the above paint film in accordance with eachangle condition can use any value as long as the value can specify acolor by expressing or computing the lightness, chroma, and hue. Forexample, it is possible to express the lightness, chroma, and hue by anXYZ color specification system (X, Y, and Z), L*a*b* color specificationsystem (L*, a*, and b* values), Hunter's color specification system (L,a, and b values), L*C*h color specification system (L* value, C* value,and h value) specified in CIE (1994), or Munsell color specificationsystem. Particularly, indication by the L*a*b* color specificationsystem or L*C*h color specification system is generally used forindication of a color in industrial fields including the automobilerepair-painting field.

Micro-brilliant-feeling Sample-color Tags (B)

[0029] Micro brilliant feeling denotes the texture of the peculiarbrilliance revealed in a paint color containing a brilliant pigment suchas aluminum powder or brilliant mica powder. For example, the microbrilliant feeling corresponds to the graininess, glittering or dazzlingfeeling, or rough texture of aluminum or mica, or size of particles. Themicro-brilliant-feeling sample-color tags (B) are used to compare apurposed paint color with the micro brilliant feeling of a referencecolor to be matched, select color tags having similar micro brilliantfeeling, and decide the micro brilliant feeling of a purposed paint filmout of the color tags. For example, the tags (B) can besystematically-arranged color tags prepared by applyingbrilliant-material-contained paints obtained by changing qualities,particle diameters, and blending quantities of brilliant materials andthereby blending the materials to a substrate and drying the paints.

[0030] Specific examples of the micro-brilliant-feeling sample-colortags (B) include a booklet and a card in which paint colors of domesticand foreign automobiles are printed for each year and each automobilemaker in the field of repair painting of automobiles.

[0031] Micro-brilliant-feeling data values, color numbers, or colornames are described in the micro-brilliant-feeling sample-color tags (B)and it is necessary that micro-brilliant-feeling data can be extractedfrom these color numbers or color names.

[0032] Though various types of data values are considered as themicro-brilliant-feeling data values, the present inventor et al. findthat micro-brilliant feelings are well matched when two parameters “MGR” and “MBV” well coincide with each other and describe a toning methodof a paint using these micro-brilliant-feeling parameters im thespecification of Japanese Patent Application No.28414/2000. “MGR” is aparameter expressing the particle feeling {perception generated byirregular non-directional patterns (random patterns) caused byorientation and overlap of brilliant pigments in paint film} and “MBV”is a parameter obtained by digitizing the glittering feeling (perceptionof irregular fine brilliancy caused by light regularly reflected frombrilliant pigment in paint film).

[0033] “MGR” and “MBV” can be respectively obtained from atwo-dimensional image formed by photographing the surface of a brilliantpaint film irradiated with light by a CCD camera.

[0034] “MGR” is computed in accordance with a two-dimensionalpower-spectrum integrated value (hereafter may be abbreviated as “IPLS”)shown by the following expression obtained by integrating the power of alow spatial frequency component in accordance with a spatial frequencyspectrum obtained by applying two-dimensional Fourier transform to theabove two-dimensional image and normalizing the integrated power by a DCcomponent.

Numerical Formula 1

[0035] Two-dimensional power-spectrum integrated value=$\frac{\int_{0}^{L}{\int_{0}^{2\pi}{{P\left( {v,\theta} \right)}{v}{\theta}}}}{P\left( {0,0} \right)}$

[0036] (In the above expression, v denotes a spatial frequency, θdenotes an angle, P denotes a power spectrum, 0 to L denote extractedlow-spatial-frequency areas, and L denotes the upper limit of anextracted frequency.)

[0037] It is also possible to evaluate “particle feeling” in accordancewith the value of MGR computed by the following linear expression inaccordance with the above two-dimensional power-spectrum integratedvalue (IPSL).

[0038] When the value of IPSL is 0.32 or more, the following expressionis effectuated.

MGR=[(IPSL×1000)−285]/2

[0039] When the value of IPSL ranges between 0.15 and 0.32 (bothexcluded), the following expression is effectuated.

MGR=[IPSL×(35/0.17)−(525/17)]/2

[0040] When the value of IPSL is 0.15 or less, the following expressionis effectuated.

MGR=0

[0041] Each of the above values of MGR is a value set to 0 when abrilliant material does not have particle feeling or a value set toapprox. 100 when the brilliant material has highest particle feeling.Thus, a material having higher “particle feeling” shows a larger value.

[0042] “MBV” is a value computed in accordance with the data obtained byanalyzing a two-dimensional image formed by photographing it by a CCDcamera by an image analyzer, which is obtained as described below.

[0043] That is, a two-dimensional image is divided into a lot of blocks,brightnesses of all the blocks are totalized to obtain a totalized valueand an average brightness x is obtained by dividing the totalized valueby all blocks to set a threshold value α to a value equal to or higherthan the average brightness x. It is generally proper that the thresholdvalue a is the sum of average brightnesses x and y (y is a value rangingbetween 24 and 40, preferably ranging between 28 and 36, more preferablyequal to 32).

[0044] Then, the threshold value a is subtracted from each of thebrightnesses of the blocks and positive subtracted values are totalizedto obtain the total volume V that is the sum of the subtracted values.Moreover, the total area S is obtained which is the total number ofblocks having a brightness equal to or larger than the threshold value α(total number of blocks having brightness equal to or higher than theabove threshold value α obtained by converting them into binary valuesin accordance with the threshold value α). The average height PHavα ofbrightness peaks is assumed as a value obtained by multiplying the valueobtained by dividing the total volume V by the total area S by 3, thatis, a value obtained from the following expression because it isconsidered that a brightness peak can be approximated to a cone orpyramid.

PHavα=3V/S

[0045] Moreover, a threshold value β is set which ranges between theabove average brightness x and the above threshold value α (bothincluded). It is proper that the threshold value β is equal to or lessthan the threshold value α and generally the sum of average brightnessesx and z (z is a value ranging between 16 and 32, preferably rangingbetween 20 and 28, more preferably equal to 4).

[0046] Then, the threshold value β is subtracted from the brightness ofeach of the above blocks and positive subtracted values are totalized toobtain the total volume W which is the sum of the subtracted values.Moreover, the total area A is obtained which is the total number ofblocks having brightness equal to or higher than the threshold value β(total number of block having brightness equal to or higher than thethreshold value β obtained by converting them into binary values inaccordance with the threshold value β). It is possible to assume theaverage height Phav β of brightness peaks at the threshold value β as avalue obtained by multiplying the value obtained by dividing the totalvolume W by the total area A by 3, that is, a value obtained from thefollowing expression because it is considered that a brightness peak canbe approximated to a cone or pyramid.

Phav β=3W/A

[0047] Moreover, it is possible to obtain the average particle area ofoptical particles from the total area A at the threshold value β and thenumber of optical particles C showing the brightness equal to or higherthan the threshold value β. In the present invention, an “opticalparticle” denotes an “independent continuum having a brightness equal toor higher than a threshold value on a two-dimensional image”. The shapeof the above optical particle is assumed as a circle and the diameter Dof a circle having an area equal to the average particle area isobtained from the following expression.

Numerical Formula 2

D={square root}{square root over ((4A/πC))}

[0048] Then, the peak skirt of average PSav of brightness peaks isobtained from the following expression in accordance with the abovePHavβ and L.

PSav=D/PHavβ

[0049] It is possible to approximately compute a brightness value BV bythe following expression in accordance with the brightness-peak averageheight Phavα and brightness-peak skirt of average PSav obtained asdescribed above.

BV=Phavα+a·PSav

[0050] (In the above expression, “a” is equal to 300 when Phavα is lessthan 25 but “a” is equal to 1,050 when PHavα exceeds 45 and is equal toa value shown by the following expression when PHavα=0 ranges between 25and 45.)

a=300+37.5×(PHavα−25)

[0051] The value of MBV can be obtained by computing it by the followinglinear expression in accordance with the above brightness value BV.

MBV=(BV−50)/2

[0052] The value of M BV is set to 0 for no glittering feeling and setto approx. 100 for highest-glittering feeling and increases for higher“glittering feeling”.

Computer (C) in Which Color-matching-computation Logic Works

[0053] A plurality of paint blendings, color data andmicro-brilliant-feeling data corresponding to the paint blendings, colorcharacteristic data and micro-brilliant-feeling characteristic data of aplurality of primary-color paints, and according to necessity, aplurality of color numbers and a plurality of paint blendingscorresponding to the color numbers are entered in the computer (C) inwhich color-matching computation logics using the paint blendings andthe data work. Moreover, it is allowed to enter micro-brilliant-feelingdata values of color numbers or color names in the computer (C)according to necessity so that micro-brilliant-feeling datacorresponding to a color number or color name can be fetched.

[0054] It is possible that the color data corresponding to each paintblending entered in the computer is the colorimetric data of a paintfilm obtained from each paint measured by a multi-angle colorimeter.

[0055] The color characteristic data values of primary-color paintsentered in the computer can be K-value (light absorption coefficient)and S-value (light scattering coefficient) of primary-color paints. Theabove K-value and S-value can be obtained by digitizing the calorimetricdata of a primary-color paint and a diluted color of the primary-colorpaint.

[0056] The above color numbers entered in the computer according tonecessity are usually color code numbers designated for eachpainted-product manufacturing maker and paint blendings for repairpainting are entered in accordance with the color numbers. In the caseof the paint blendings, one paint blending can correspond to one colornumber. However, actual blendings can be included and it is allowed toenter a plurality of paint blendings. Moreover, the colorimetric data offormed paint films measured by a multi-angle colorimeter are previouslyentered in the computer.

[0057] A computer toning method of the present invention includes twomodes such as a first toning method which does not have a step ofselecting a paint blending out of the same color numbers by using acolor number and a second toning method which has a step of selecting apaint blending out of the same color numbers by using a color number.

[0058] First, the first toning method is described in accordance withsteps in order.

[0059] Step (1):

[0060] Step (1) is a step of measuring the paint film of a referencecolor with which the color of a paint should be matched through toningby the above calorimeter (A) and obtaining the color data of thereference color.

[0061] It is preferable to obtain color data under the above angleconditions by measuring the reference color which is the color of apaint film with which a paint color should be matched by the multi-anglecalorimeter. When forming a repair paint film in repair painting such asautomobile repair paining, it is necessary that the difference betweenthe color of the paint film of a repair-painting portion and the colorof a paint film nearby the repair-painting portion is not easilyvisually recognized. Therefore, it is normally suitable that the abovereference color is the color of the paint film nearby therepair-painting portion.

[0062] Step (2)

[0063] Step (2) is a step of comparing the above reference color withthe above micro-brilliant-feeling sample-color tags (B) and deciding themicro-brilliant-feeling data of the reference color. Usually, a colortag probably nearest to the micro-brilliant feeling of the referencecolor is selected out of the micro-brilliant sample-color tags (B) todecide the micro-brilliant-feeling data in accordance with the selectedcolor tag. It is also allowed to record micro-brilliant-feeling data andthe bending ratio of brilliant materials in each color tag or it isallowed to separately obtain micro-brilliant-feeling data and theblending ratio of brilliant materials from the color number or colorname of the paint color on each color tag.

[0064] Step (3)

[0065] In step (3) , a prospective paint blending is selected bycomparing the color data of the reference color obtained in the abovestep (1) and the micro-brilliant feeling of the reference color obtainedin the above step (2) with the color data and micro-brilliant-feelingdata corresponding to paint blendings previously entered in a computerand indexing the matching degree between the color and themicro-brilliant feeling of the entered paint blending. It is possible toproperly select a prospective paint blending which may be the mostrational by considering the matching degree of the color andmicro-brilliant feeling with a reference color and the blending data.The above selection method is not restricted. It is preferable to selecta prospective paint blending out of blendings in which the matchingdegree of the color difference and micro-brilliant feeling with areference color is kept in a certain range.

[0066] Though the first toning method uses the above steps (1), (2), and(3) as indispensable steps, it is also allowed to execute the followingstep (4) after step (3) in order to make a color further approach to areference color.

[0067] Step (4)

[0068] Step (4) is a step of obtaining a corrected blending made tofurther approach to a reference color by using a computer in which aplurality of paint blendings, color data and micro-brilliant-feelingdata corresponding to each of the paint blendings, and colorcharacteristic data and micro-brilliant-feeling characteristic data of aplurality of primary-color paints are entered and thereby correcting theprospective paint blending selected in step (3) by acolor-matching-computation logic using the above paint blendings anddata.

[0069] It is also allowed that the first toning method further includesa step of transferring the prospective paint blending obtained in theabove step (3) or the corrected blending obtained in step (4) to anelectronic balance.

[0070] Then, the second toning method is described below.

[0071] In the case of the second toning method, the following steps (5)to (7) are executed by further using a plurality of entered colornumbers and paint blendings corresponding to the color numbers as thedata entered in the computer used for the above first toning method.

[0072] Step (5)

[0073] Step (5) is a step same as step (1) for the first toning method.

[0074] Step (6)

[0075] Step (6) is a step same as step (2) for the first toning method.

[0076] Step (7)

[0077] In step (7), a prospective paint blending is selected byselecting the color data and micro-brilliant-feeling data of at leastone paint blending having a color number same as the color number of areference color out of color numbers previously entered in a computer,comparing the color data and micro-brilliant-feeling data of theselected paint blending with the color data and micro-brilliant feelingof the reference color, and indexing the matching degree of the colorand micro-brilliant feeling of the selected paint blending. It ispossible to properly select a prospective paint blending which may bethe most rational by considering the matching degree of a referencecolor and micro-brilliant feeling with a reference color and blendingdata.

[0078] Though the second toning method uses the above steps (5), (6),and (7) as indispensable steps, it is allowed to execute the followingstep (8) after step (7) in order to make a color further approach to areference color.

[0079] Step (8)

[0080] Step (8) is a step same as step (4) for the first toning methodand a step of correcting the prospective paint blending selected in step(7) and obtaining a corrected blending made to further approach to areference color.

[0081] It is allowed that the second toning method further includes astep of transferring the prospective paint blending obtained in theabove step (7) or the corrected blending obtained in step (8) to anelectronic balance.

[0082] In the case of the above first and second toning methods, it ispossible to transfer a blending to an electronic balance through atelephone line or an optical cable. It is possible to blend toningpaints in accordance with the transferred blending by using anelectronic balance. By preparing a toned-paint plate coated with thetoning paint, it is possible to determine whether the paint isacceptable. If it is not acceptable, it is possible to obtain acorrected blending again by operating a color-matching-computation logicin accordance with the bending of the toning paint and the color dataand micro-brilliant-feeling data of the toned-paint plate.

EMBODIMENT

[0083] The present invention is further specifically described below byreferring to embodiments. However, the present invention is notrestricted to the embodiments.

Apparatus Used and Measuring Method

[0084] In the case of the following embodiments, a reference color withwhich the color of a paint should be matched through toning is measuredby a multi-angle colorimeter “Van-VanFA Sensor” made by KANSAI PAINTCO., LTD. and a computer in which color characteristic data andmicro-brilliant-feeling characteristic data of a plurality of primarycolor paints are entered and a color-matching-computation logic usingblendings of the paints and the data values works uses the computercolor-matching system “Van-VanFA Station” made by KANSAI PAINT CO., LTD.The above “Van-VanFA Sensor” can obtain a color-measured value bymeasuring data under three-angle conditions in which angles formedbetween a mirror-surface reflection axis and a light-receiving axis are25°, 45°, and 75°.

[0085] Micro-brilliant-feeling sample-color tags use the “Auto Color”made by KANSAI PAINT CO., LTD. The “Auto Color” is a booklet in whichpaint colors of domestic and foreign automobiles are printed for eachyear and each automobile maker to compare micro-brilliant feelingsbetween a reference color and a same-color-based paint color printed inthe “Auto Color” and select a paint color closest to the referencecolor. The micro-brilliant-feeling measured value of the selected paintcolor is stored in the database of the “Van-VanFA Station”.

EMBODIMENT

[0086] Reference colors of the paint film surface of automobiles includethree colors such as high-lightness silver metallic (silver M1),middle-lightness green metallic pearl (green MP), and low-lightness bluepearl (blue P).

[0087] Color measured values of the above three reference colors underthree angle conditions are shown below. TABLE 1 Light-receiving ColorAngle L* a* b* Silver M1 250 99.96 −1.48 −0.65 45° 65.34 −0.96 −2.17 75°42.02 −0.78 −2.38 Green MP 25° 52.28 −48.18 −10.80 45° 30.39 −32.89−11.31 75° 15.97 −22.03 −10.87 Blue P 25° 15.23 −1.57 −9.57 45° 3.210.32 −3.68 75° 1.10 0.58 −1.08

[0088] Moreover, the following are micro-brilliant-feeling data values(MGR and MBV) of most approximate paint colors selected out of AutoColor. In Table 2, MGR is a parameter obtained by digitizing particlefeeling and MBV is a parameter obtained by digitizing glitteringfeeling. TABLE 2 Color MGR MBV Approximate color of silver M1 62.8947.38 Approximate color of green MP 56.50 40.50 Approximate color ofblue P 59.82 40.20

[0089] The following are quantities of primary-color paints (paintblendings) computed by the computer color-matching system in accordancewith micro-brilliant-feeling data values of most-approximate paintcolors selected out of measured values under three angle conditions ofthe above three reference colors and Auto Color. Silver M1 Type ofprimary-color paint Weight ratio Silver A (Metallic primary color A)41.1 Silver B (Metallic primary color B) 35.3 Black A (Black primarycolor A) 0.9 Blue A (Blue primary color A) 0.4 Assistant A (Aluminumorientation regulator A) 18.8 Assistant B (Aluminum orientationregulator B) 3.5

[0090] Green MP Type of primary-color paint Weight ratio Blue A (Blueprimary color A) 42.0 Green A (Green primary color A) 24.0 Silver C(Metallic primary color C) 15.5 Blue B (Blue primary color B) 5.0 PearlA (Pearl primary color A) 2.1 Maroon A (Reddish-brown primary color A)1.3 Assistant A (Aluminum orientation regulator A) 8.4 Assistant B(Aluminum orientation regulator B) 1.7

[0091] Blue P Type of primary-color paint Weight ratio Black B (Blackprimary color B) 39.2 Blue C (Blue primary color C) 22.3 Blue D (Blueprimary color D) 19.1 Pearl B (Pearl primary color B) 10.5 Pearl C(Pearl primary color C) 8.9

[0092] Toned-paint plates are prepared in accordance with the abovepaint blendings. The following able shows measured values of referencecolors and colors of the above toned-paint plates in the L*a*b* colorsystem when performing three-angle-condition measurement by the abovemulti-angle calorimeter. TABLE 3 Light-receiving Color Angle ΔL* Δa* Δb*ΔE* Silver M1 25° 3.86 0.08 1.03 4.00 45° 1.78 0.09 0.96 2.02 75° 0.60−0.03 1.23 1.37 Green MP 25° 2.01 0.48 −2.77 3.46 45° 1.40 0.77 −2.232.75 75° 0.68 1.08 −1.51 1.98 Blue P 25° 3.56 −0.36 −1.16 3.77 45° 1.90−0.25 −1.94 2.73 75° 0.68 −0.06 −0.59 0.90

[0093] The micro-brilliant feelings of the toned-paint plates andreference colors are well matched each other. However, color differencesbetween measured values of paint colors of the toned-paint plates andmeasured values of reference colors are large and moreover, differencesare detected in visual determination. Therefore, quantities ofprimary-color paints (additional designated quantities) required tocorrect colors of paints to be toned in accordance with color measuredvalues at various angles on the toned-paint plates are computed by thecomputer color-matching system. Moreover, the following are the thenadditional designated quantities to 100 parts by weight of the abovetoned paints. Silver M1 Type of primary-color paint Part by weight BlackA (Black primary color A) 3.9 Assistant A (Aluminum orientationregulator A) 0.9 Assistant B (Aluminum orientation regulator B) 0.2

[0094] Green MP Type of primary color paint Part by weight Green A(Green primary color A) 7.5 Assistant A (Aluminum orientation regulatorA) 0.5 Assistant B (Aluminum orientation regulator B) 0.9 Yellow A(Yellow primary color A) 1.3

[0095] Blue P Type of primary-color paint Part by weight Black B (Blackprimary color B) 17.2 Blue C (Blue primary color C) 7.5

[0096] The following Table 4 shows values of ΔL*, Δa*, Δb*, and ΔE* fromreference colors when measuring toned-paint plates obtained by paintingthe plates with paints corrected by the above additional designatedquantities by a multi-angle colorimeter at various angle conditions.TABLE 4 Light-receiving Color Angle ΔL* Δa* Δb* ΔE* Silver M1 25° 0.92−0.01 −0.12 0.93 45° 0.29 −0.01 −0.07 0.30 75° −0.30 −0.08 −0.16 0.34Green MP 25° −0.07 0.61 0.54 0.82 45° −0.15 0.07 0.42 0.45 75° −0.04−0.26 0.29 0.39 Blue P 25° −1.36 0.31 0.72 1.57 45° −0.57 0.12 0.87 1.0575° −0.13 −0.01 0.25 0.29

[0097] Because color differences between measured values of paints ofthese corrected toned-paint plates and reference colors are small andresults of color determination and micro-brilliant feeling determinationthrough visual observation are acceptable. Therefore, repair painting isapplied to an automobile by using corrected toning paints to visuallyperform equal color determination for repair painted portions of theautomobile and paint-film surfaces nearby the portions and resultantly,preferable color matching is obtained.

[0098] The following Table 5 shows results of confirming micro-brilliantfeeling data values of micro-brilliant-feeling sample-color tags andcorrected-paint plates. Micro-brilliant-feeling data values ofreferences colors and corrected toned-paint plates are measured by amicro-brilliant-feeling measuring instrument for laboratory use made byMINOLTA CO., LTD. to process electronic images by a computer. TABLE 5Color MGR MBV Silver M1 Reference color 60.20 44.55Micro-brilliant-feeling 62.89 47.38 sample-color tag Correctedtoned-paint 62.34 46.88 Plate Green MP Reference color 58.00 42.63Micro-brilliant-feeling 56.50 40.50 sample-color tag Correctedtoned-paint 56.39 40.36 Plate Blue P Reference color 59.10 38.97Micro-brilliant-feeling 59.82 40.20 sample-color tag Correctedtoned-paint 58.57 39.92 Plate

[0099] As clarified by values of micro-brilliant-feeling parameters MGRand MBV shown in the above Table 5, differences between values of MGRand MBV in reference colors, micro-brilliant-feeling sample-color tags,and corrected toned-paint plates are kept within ±3 for all paint colors(in general, a person recognizes the difference between values ofmicro-brilliant-feeling parameters MGR and MBV when the differenceexceeds 3) and micro-brilliant feelings are also numerically matched.

[0100] A computer paint-toning method of the present invention allows animmature toning person to tone colors having brilliant feeling at a highaccuracy.

1. A toning method of a paint having brilliant feeling characterized byexecuting the following steps (1) to (3) by a computer toning apparatusconstituted by (A) a colorimeter, (B) micro-brilliant-feelingsample-color tags, and (C) a computer in which a plurality of paintblendings, color data and micro-brilliant-feeling data corresponding tothe paint blendings, and color characteristic data andmicro-brilliant-feeling data of a plurality of primary-color paints areentered and a color-matching-computation logic using said paintblendings and data values works: (1) a step of measuring a referencecolor with which the color of a paint should be matched through toningby a colorimeter and obtaining color data of the reference color; (2) astep of comparing said reference color with micro-brilliant-feelingsample-color tags and deciding the micro-brilliant feeling of saidreference color; and (3) a step of comparing the color data andmicro-brilliant feeling of said reference color with the color data andmicro-brilliant-feeling data corresponding to paint blendings previouslyentered in a computer, indexing matching degrees between colors andmicro-brilliant feelings of said entered paint blendings, and selectinga prospective paint blending.
 2. The toning method according to claim 1,further characterized by executing (4) a step of correcting a selectedprospective paint blending by a color-matching logic and obtaining acorrected blending closer to a reference color after said step (3). 3.The toning method according to claim 1 or 2, characterized bytransferring said prospective paint blending obtained in step (3) orsaid corrected blending obtained in step (4) to an electronic balance.4. A toning method of a paint having brilliant feeling characterized byexecuting the following steps (5) to (7) by a computer toning apparatusconstituted by (A) a calorimeter, (B) micro-brilliant-feelingsample-color tags, and (C) a computer in which a plurality of colornumbers, paint blendings corresponding to said color numbers, color dataand micro-brilliant-feeling data corresponding to said paint blendings,and color characteristic data and micro-brilliant-feeling characteristicdata of a plurality of primary-color paints are entered and acolor-matching logic using said paint blendings and said data works: (5)a step of measuring a reference color with which a paint color should bematched through toning by a colorimeter and obtaining the color data ofsaid reference color; (6) a step of comparing said reference color withmicro-brilliant-feeling sample-color tags and deciding themicro-brilliant feeling said reference color; and (7) a step ofselecting the color data and micro-brilliant-feeling data of at leastone paint blending having a color number same as the preset color numberof said reference color, comparing the color data andmicro-brilliant-feeling data of said selected paint blending with thecolor data and micro-brilliant-feeling of said reference color, indexingthe matching degree between the color and micro-brilliant feeling ofsaid selected paint pant blending, and selecting a prospective paintblending.
 5. The toning method according to claim 4, characterized byfurther executing (8) a step of correcting said selected prospectivepaint blending by a color-matching logic and obtaining a correctedblending closer to said reference color after said step (7).
 6. Thetoning method according to claim 4 or 5, characterized by furthertransferring said prospective paint blending obtained in step (7) orsaid corrected blending obtained in step (8) to an electronic balance.